vault backup: 2024-01-01 23:08:40

Databases/SurrealDB/Syntax.md

@@ -31,4 +31,47 @@ SELECT name AS user_name, address FROM person;
 SELECT * FROM ONLY person:john;
 ```
 
+### Advanced `SELECT` expressions
+
+```SQL
+-- Select nested objects/values
+SELECT address.city FROM person;
+
+-- Select all nested array values
+-- note the .* syntax works to select everything from an array or object-like values
+SELECT address.*.coordinates AS coordinates FROM person;
+-- Equivalent to 
+SELECT address.coordinates AS coordinates FROM person;
+
+-- Select one item from an array
+SELECT address.coordinates[0] AS latitude FROM person;
+
+-- Select unique values from an array
+SELECT array::distinct(tags) FROM article;
+
+-- Select unique values from a nested array across an entire table
+SELECT array::group(tags) AS tags FROM article GROUP ALL;
+
+-- Use mathematical calculations in a select expression
+SELECT ( ( celsius * 2 ) + 30 ) AS fahrenheit FROM temperature;
+
+-- Return boolean expressions with an alias
+SELECT rating >= 4 as positive FROM review;
+
+-- Select manually generated object structure
+SELECT { weekly: false, monthly: true } AS `marketing settings` FROM user;
+
+-- Select filtered nested array values
+SELECT address[WHERE active = true] FROM person;
+
+-- Select a person who has reacted to a post using a celebration
+-- You can see the graph as: person->(reacted_to WHERE type='celebrate')->post
+SELECT * FROM person WHERE ->(reacted_to WHERE type='celebrate')->post;
+
+-- Select a remote field from connected out graph edges
+SELECT ->likes->friend.name AS friends FROM person:tobie;
+
+-- Use the result of a subquery as a returned field
+SELECT *, (SELECT * FROM events WHERE type = 'activity' LIMIT 5) AS history FROM user;
+```
 ###